Supreme Court day four, lunchtime briefing: enormous questions about power and legal writ loom over this appeal

Gina Miller arriving at the Supreme Court for the final day of the Article 50 caseCredit:
Andy Rain/EPA

The fourth and final day of the Supreme Court’s great Brexit hearing began with an unanswered question hanging in the air: should this case be happening at all? For some reason the Government never challenged the justiciability of Gina Miller’s application to block the use of the executive prerogative to trigger Article 50.

Jeremy Wright, the Attorney-General, said at the outset that it was accepted there was a “legal question” to be considered, namely whether only an Act of Parliament can begin the process to withdraw the United Kingdom from the EU because so many laws are tied to membership.

But even as the case has unfolded before an unprecedented panel of all 11 judges, across Parliament Square in the House of Commons MPs were making it quite plain that they were able to reach their own decisions without being told what to do by the courts. There may be legal points at issue; but arguably this...